The present invention relates to measuring, imaging, and mapping of intra-oral objects and features and, more particularly, to a method and system for real time intra-orally acquiring and registering three-dimensional measurements and images of intra-oral objects and features, for primary application in the field of dentistry.
Commercial application of non-x-ray based imaging methods, devices, and systems in the field of dentistry, for automatically measuring, imaging, and mapping dental conditions of patients, is still significantly limited, even in view of the current rapid rate of developing and applying a wide variety of non-x-ray based imaging techniques in various other fields. The main objective, and benefit, of using automatic measuring and imaging techniques in dentistry, hereinafter also referred to as xe2x80x98dental measuring/imagingxe2x80x99, is to enable dental practitioners such as dentists, dental hygienists, and dental technicians to obtain highly accurate and precise realistic measurements, images, and spatial maps of intra-oral objects and features such as teeth, gum, intra-oral soft tissue, bone matter, dental undercuts, and, dental fixtures and prostheses of any kind, of dental patients, for the goal of improving procedures and processes, and decreasing costs, relating to examining, charting, diagnosing, and treating dental conditions of those patients.
Details of limitations and shortcomings associated with conventional non-imaging techniques currently used for examining, charting, diagnosing, and treating dental conditions of patients, in general, and for designing, manufacturing, fitting, and monitoring dental prostheses, in particular, are adequately described in dental literature and related prior art, for example, in U.S. Pat. No. 5,440,393, issued to Wenz, in PCT International Publication No. WO 98/52493, in U.S. Pat. No. 5,273,429, issued to Rekow et al., in U.S. Pat. No. 4,964,770, issued to Steinbichler et al., and in U.S. Pat. No. 5,857,853, issued to van Nifterick et al.
A well known example illustrating the potentially significant utility, effectiveness, and, procedural and economic impact of successfully applying automatic measuring and imaging techniques to dentistry involves examining, charting, diagnosing, and treating dental patients requiring dental prostheses such as crowns, bridges, dentures, or implants. More specifically, data and information obtained from measuring, imaging, and mapping intra-oral objects and features can be directly used for highly accurately and cost effectively designing, manufacturing, fitting, and monitoring dental prostheses, thereby replacing currently used inaccurate, labor, material, time, and cost intensive, non-imaging techniques. Automatic dental measuring and imaging techniques are also applicable for performing various types of restorative procedures, occlusal registration, and, orthodontic and tempero mandibular joint (TMJ) dysfunction therapies.
Different categories of mechanisms, such as electrical, electronic, electromechanical, electro-optical, electromagnetic, radar, magnetic, magneto-mechanical, magnetic resonance, acoustic, ultrasound, sonar, photo-acoustic, telemetry, hybrids, and combinations of these, used for automatic three-dimensional measurement, imaging, and mapping of objects, features, and distances, are widely known and employed in various fields. The particular category of electro-optical mechanisms used in measuring and imaging techniques includes, for example, time/light in flight, laser scanning, moire, laser speckle pattern sectioning, interferometry, photogrammetry, laser tracking, and structured light or active triangulation. Specialized interferometric techniques of shearography, diffraction grating, digital wavefront reconstruction and wavelength scanning, and conoscopic holography have recently been developed as useful electro-optical measuring, imaging, and mapping techniques. Electro-optical techniques are reviewed by Chen, F., in xe2x80x9cOverview of three-dimensional shape measurement using optical methodsxe2x80x9d, Opt. Eng. 39(1) Jan., 10-22, 2000, and are further described in references therein. Several of these electro-optical techniques have been specifically applied for measuring, imaging, and mapping intra-oral objects and features. Magnetic resonance and ultrasound imaging techniques are well developed and especially applied in the medical field.
Basic in any measuring and imaging technique for accurately and precisely measuring, imaging, or mapping objects and features is the determination, sub-division, and usage of the source space and source resolution associated with the measurements and images. Measurements and images are defined in terms of global and local coordinates of the source space. Global space refers to a global coordinate space, encompassing one or more local coordinate spaces, and is at source resolution. Local space refers to a local coordinate space that is contained within global space that is also at source resolution. Accordingly, by definition, each local coordinate space and all coordinate points or positions contained therein are local with respect to the global coordinate space, whereby they can be transformed, mapped, or related to corresponding global coordinate space and global coordinate points or positions, respectively. This procedure is commonly known as registration of local coordinate space and associated local coordinate points or positions with respect to, or in terms of, global coordinate space and associated global coordinate points or positions, within source space. The registration procedure is performed by using one or more reference, fiducial, or registration, points or markers defined in the global coordinate space, which can also be associated with one or more local coordinate spaces within the global coordinate space.
Hereinafter, the terms xe2x80x98measuring systemxe2x80x99, xe2x80x98measuring devicexe2x80x99, xe2x80x98imaging systemxe2x80x99, and xe2x80x98imaging devicexe2x80x99 are general, and are applicable to any category, such as those listed above, of automatic three-dimensional shape measurement, imaging, and mapping of objects and features. With respect to measuring, imaging, and mapping objects and features, the position and orientation of a measuring and imaging device such as an electro-optical measuring and imaging probe, an electromagnetic measuring and imaging probe, an ultrasound measuring and imaging probe, or a magnetic resonance measuring and imaging probe, can be characterized, described, or defined in terms of source or global coordinate space. Furthermore, for each measuring and imaging device global position, each field of view of the measuring and imaging device can be associated with a corresponding local coordinate space, within the source or global coordinate space, where the positions, orientations, and shapes or configurations, of the objects and features in each field of view of the measuring and imaging device are definable in terms of that local coordinate space. Applying a registration procedure here involves transforming or mapping local measurement and image data and information of the objects and features to global measurement and image data and information of the objects and features, using the position and orientation of the measuring and imaging device in global coordinate space as the transforming or mapping common link between global and local coordinate spaces.
Implementation of an automatic measuring and imaging technique usually includes measurement and image processing hardware and software, for automatically performing mathematical operations involved in registering local with global coordinate spaces during and/or after measurement and imaging, and for manipulating and editing measurements and images acquired in local and/or global coordinate spaces. Following these procedures, the graphical or digitized measurements and images are displayed on a display device by converting measurement and image definition from source space into device space, where device space refers to the characteristics of the device, for example, device units or pixels, by which measurements and images are displayed.
In a given automatic measuring and imaging technique, some form of one of the following three methods, object rotation method, measuring and imaging device transport method, and, fixed measuring and imaging system with multiple measuring and imaging devices method, is usually employed for the three-dimensional measuring and imaging of objects and features. In particular, in the measuring and imaging device transport method, registration of coordinate spaces, and, measurement and imaging are typically performed at a number of different fields of view of the measuring and imaging device, according to the desired extent of measuring and imaging the objects and features in the source space. Measurement and image data and information are transformed from local coordinate spaces into the global or source coordinate space using an appropriate registration procedure. Measurements and images are subsequently pieced or merged together, using an appropriate best fit algorithm, for forming composite measurements and images, or maps, of the objects and features of interest, followed by converting measurement and image, and/or map, definition from source space into device space for displaying and/or storing the measurements and images, and/or maps, of the objects and features.
Three-dimensional shape measurement, imaging, and mapping of objects and features, such as intra-oral objects and features, requires the positioning of at least one measuring and imaging device such as an electro-optical measuring and imaging probe, an electromagnetic measuring and imaging probe, an ultrasound measuring and imaging probe, or a magnetic resonance measuring and imaging probe, at different locations within source or global coordinate space, such as the oral cavity or mouth of a dental patient. Accordingly, each global location of the measuring and imaging device is associated with one or more fields of view, where each field of view is characterized or described by a corresponding local coordinate space, within the global coordinate space, and where the positions, orientations, and shapes or configurations, of objects and features of interest such as teeth, gum, intra-oral soft tissue, and dental fixtures or prostheses of any kind, are definable in terms of that local coordinate space.
In order to register point clouds or, measuring and imaging data associated with objects and features located in such local coordinate spaces, in terms of the global coordinate space, each measuring and imaging device coordinate system location and orientation must be accurately and precisely known or measured. Any error in measuring and/or calculating the measuring and imaging device location and orientation causes propagation error in the registration procedure, thereby decreasing accuracy and precision of final output data and information, such as measurements and images, and/or maps, of the particular objects and features of interest.
Various methods are available for enabling the performing of the registration procedure between local and global coordinate spaces, where a particular method used is compatible with a particular measuring and imaging technique, such as those in the above list of categories of automatic three-dimensional shape measurement, imaging, and mapping of objects and features. Commonly used methods for performing the registration procedure are based on: (1) electromechanical location and orientation of the measuring and imaging device, whereby the measuring and imaging device is attached to, or are part of, a highly accurate and precise electromechanical system used for moving and fixing the positions of the measuring and imaging device throughout source or global coordinate space, (2) photogrammetry, also known as pattern recognition, of reference, fiducial, or registration, points or markers accurately located and fixed, and necessarily visible by the measuring and imaging device in the same field of view, or local coordinate space, of the particular objects and features being measured and imaged, (3) optical tracking of each measuring and imaging device location and/or orientation, whereby active or passive optical targets associated with local coordinate spaces defined within source or global coordinate space, are attached to, or part of, each measuring and imaging device, using an optical tracker system, and (4) hybrids of these methods.
Exemplary prior art electro-optical based methods, devices, and systems, each operating with some form of one of the above described registration procedures, for measuring, imaging and mapping intra-oral objects and features, with particular application to dentistry, are briefly summarized below.
In U.S. Pat. No. 4,935,635, issued to O""Harra, there is disclosed a three-dimensional measuring system particularly for dental and other space-limited uses, featuring a laser diode projecting a triangulating beam which scans the surface of intra-oral objects and features, such as a tooth, to be imaged and mapped. Preferably, in a given field of view, three teeth are scanned at a time, with resolution or accuracy of at least fifty microns. The registration procedure is based on the method of electromechanical location and orientation of a mostly extra-orally located imaging device including a probe, highly accurate axial stepping motors, a scanning laser beam, and photodetectors.
In U.S. Pat. No. 4,964,770, issued to Steinbichler et al., there is disclosed a process of making artificial teeth, featuring the use of interferometry, moire and laser scanning imaging methods. Three-dimensional shapes of the ground tooth and of the required artificial tooth are computed in accordance with an optic-geometric formula relating pixel parameters of intensity, background brightness, contrast, and angle. Description is provided for optically imaging only a single ground tooth and non-specific adjacent surfaces. The registration procedure is based on the method of electromechanical location and orientation of components of an extra-orally located imaging system including a light projector, diffraction grating, and a video camera.
In U.S. Pat. No. 5,372,502, issued to Massen et al., there is disclosed an optical probe and method for intra-oral three-dimensional surveying of teeth, including the use of a mobile two-dimensional LCD matrix plate pattern projection unit, optic fibers projecting patterned light beams into the oral cavity, and a CCD matrix image sensor, operating in accordance with moire, phase-shift, triangulation, and photogrammetry techniques. Through a comparison between the undistorted pattern projected by the probe and the distorted pattern reflected from the specific area within the oral cavity, topographical information of the imaged teeth is obtained. A formal registration procedure relating local coordinate spaces of the projected and reflected patterns to source or global coordinate space of the oral cavity is not described in this disclosure, however, it is indicated that instead of using accurately controllable axial mechanical diffraction gratings, supposedly for enabling registration of local coordinate spaces, the surveying procedure is repeated a number of times, whereby accuracy of the imaging data and information is improved by iteration. Overall accuracy and precision of the method are directly dependent upon the extent of simultaneous non-movement of both the optical probe and of the patient during surveying each specific intra-oral region.
In U.S. Pat. No. 5,386,292, issued to Massen et al., there is disclosed a method for correcting imaging errors due to non-optimal reflection qualities of teeth, during three-dimensional optical measurement and imaging of teeth, featuring the use of a light pattern projector and an imaging device such as a CCD matrix image sensor, operating in accordance with moire, phase-shift, and triangulation techniques. Correction is based on determining the angle of incidence of the measuring rays on the surface of a tooth. The registration procedure is based on the method of electromechanical location and orientation of mostly extra-orally located imaging equipment.
In U.S. Pat. No. 5,413,481, issued to Goppel et al., there is disclosed a method and apparatus for manufacturing fitting members, such as for a dental prosthesis, featuring the use of a CCD matrix camera for photographing moire fringes resulting from repeatedly projecting an optical groove grating in a slightly offset manner onto a prepared tooth stump. Description is provided for optically imaging only a single tooth stump. The registration procedure is based on the method of electromechanical location and orientation of components of an essentially extra-orally located imaging system including a projector device, a grating, mirrors, and, stepping motors and springs for fine positional control of the grating.
In U.S. Pat. No. 5,440,393, issued to Wenz, there is disclosed a process and device for measuring the dimensions of a buccal cavity having upper and lower dentition, featuring the use of variable forms of a partly intra-oral optical radiation projection scanning device including light interference and deflection elements, and, an optical signal recording and digitizing system, operating in accordance with photogrammetry, triangulation, and holography techniques. Alternative registration procedures are used, including the method of electromechanical location and orientation of components of the scanning device, and photogrammetry. For photogrammetric registration, the position and orientation of the scanning device are determined relative to the dentition of the buccal cavity, by using an extra-orally located and fixed patient skull frame device supporting three lead balls functioning as reference, or registration, points accurately located and fixed, and necessarily visible by the scanning device, in the same field of view, or local coordinate space, of each image of the buccal cavity.
In U.S. Pat. No. 5,237,998, issued to Duret et al., there is disclosed a method for correlating three-dimensional images of dental arcades, for example, a tooth stump surrounded by two healthy teeth, by correlating intra-oral imaging data of a dental impression of the arcade in the occlusive position with that of the arcade without impression material, where three mutually spaced apart reference points are located and fixed in the immediate vicinity of the arcade. The registration procedure is based on the method of photogrammetry, whereby an intra-oral device featuring a clamp or bar is used for supporting three small spheres functioning as the three reference, or registration, points, accurately located and fixed, and necessarily visible by an imaging device, in the same field of view, or local coordinate space, of every image of the dental arcade.
In U.S. Pat. No. 5,857,853, issued to van Nifterick et al., there is disclosed a method and system for automatically manufacturing a prosthesis to be fixed to implants in the jawbone of a patient, including an intra-oral imaging technique featuring the use of at least one camera positioned at the opened mouth of the patient for three-dimensionally imaging each implant from at least two different oral positions. The registration procedure is based on the method of photogrammetry, whereby 100-150 micron diameter optical recognition points engraved into intra-oral inserts accurately located and fixed onto, and projecting above, each implant, function as the reference, or registration, points, necessarily visible by the camera, in the same field of view, or local coordinate space, of every image of an implant.
To date, the inventor is unaware of a registration procedure based on optical tracking, or based on any type of automatic tracking, featuring wired and/or wireless signal communication mechanisms, of a measuring and imaging device location and/or orientation for implementing a dental measuring and imaging technique.
It is apparent in view of the prior art, that current registration procedures used for implementing dental measuring and imaging techniques are typically based on either electromechanical location and orientation of the measuring and imaging device in source or global coordinate space relative to the intra-oral objects and features being measured or imaged in local coordinate spaces, or, photogrammetry or pattern recognition, of reference, fiducial, or registration, points or markers accurately located and fixed in source or global coordinate space, and necessarily visible by the measuring and imaging device in the same field of view, or local coordinate space, of the particular objects and features being measured or imaged. In general, each of these registration procedures particularly used in dental measuring and imaging has significant limitations, which may be a primary reason for the current relatively worldwide low volume application of non-x-ray based commercial dental measuring and imaging systems.
Electro-mechanical based registration procedures inherently involve the design, manufacture, real time hands-on operation, and maintenance of highly accurate, precise, complex, and expensive, electromechanical devices, mechanisms, components, and elements for enabling proper positional and orientational control of the measuring and imaging device relative to the objects and features of the oral cavity of the dental patient. Moreover, an operator must skillfully, and timely, during a patient visit, adjust the electro-mechanics for re-positioning the measuring and imaging device in order to change fields of view, clearly required for measuring and imaging a plurality, especially a panoramic or complete set, of intra-oral objects and features located throughout the oral cavity of the patient.
A particular limitation of employing electromechanical based registration procedures occurs each time the patient or measuring and imaging device moves immediately prior to or during the measuring and imaging process, whereby, the operator must adjust the electro-mechanics for re-positioning the measuring and imaging device, in order to re-establish the global coordinates of the measuring and imaging device, consequently involving re-registration of local coordinates relative to the new global coordinates.
Photogrammetry or pattern recognition based registration procedures do not require the extent of complex and expensive electromechanical hardware and/or software, however, by definition, the reference, fiducial, or registration, points or markers accurately located and fixed, and necessarily visible by the measuring and imaging device, in the same field of view, or local coordinate space, of one particular set of intra-oral objects and features being measured and imaged, must skillfully, and timely, during a patient visit, be re-positioned in the same field of view of each other particular set of intra-oral objects and features being measured and imaged by an operator. Similar to electromechanical based registration procedures, the re-positioning procedure is clearly required for measuring and imaging a plurality, especially a panoramic or complete set, of intra-oral objects and features located throughout the oral cavity of the patient.
Another particular limitation of employing photogrammetry based registration procedures is that reference, fiducial, or registration, points or markers, need to be of proper color, dimensions and shapes or configurations in order to be properly located, fixed, and distinguishable in a variety of relatively small local coordinate spaces associated with the intra-oral objects and features. Moreover, different colors, sizes and shapes or configurations of the points or markers may need to be used for measuring and imaging the intra-oral objects and features of a single patient, according to the particular intra-oral geometric topography of the patient, and/or according to the extent of dental measuring and imaging needed by the patient.
Additional significant limitations of current dental measuring and imaging techniques in general, which are particularly relevant to the design, manufacture, and fitting, of dental fixtures or prostheses, relate to three-dimensional measuring and measuring and imaging of intra-oral objects and features having one or more undercuts and/or color and shape or structural gradients.
In the field of dentistry, an xe2x80x98intra-oral undercutxe2x80x99, or equivalently, an xe2x80x98undercutxe2x80x99, is properly defined in terms of the following description. If a vertical plane is brought into contact with a curved surface, where the curved surface includes smooth and rough portions, such as the surface of intra-oral objects and features including topological projections, the vertical plane will contact the surface at local maxima points of convexity. If such a curved surface is rotated, while remaining in contact with the vertical plane, an outline is traced corresponding to the maximum perimeter of the curved surface. The region of the curved surface, for example, the region of the surface of intra-oral objects and features, above the outline is referred to as the xe2x80x98non-undercutxe2x80x99 region, and the region below the outline is referred to as the xe2x80x98undercutxe2x80x99 region.
The extent of an intra-oral undercut region varies according to the tilt or angle of the particular intra-oral objects and features in relation to the vertical line. With respect to performing a restorative procedure on intra-oral objects and features, generally, one vertical approach is used for examining and imaging each field of view of the intra-oral objects and features, and subsequently, restoration of the intra-oral objects and features. Therefore, in actuality, as intra-oral objects and features are titled toward or away from each other, an undercut region is essentially always present. For intra-oral objects and features prepared for a restorative procedure, the main strategy is to eliminate undercut regions in restoration preparations by cutting or drilling the target intra-oral objects and features, and filling in undercuts with restorative material, for forming a common xe2x80x98vertical viewxe2x80x99, also known as a common xe2x80x98path of insertionxe2x80x99. In dental practice, however, it is not always possible to perform such ideal restorative preparations.
In dental practice, an undercut can also be referred to as the surface of intra-oral objects and features which, upon removal of set dental impression material from the vicinity of the intra-oral objects and features, causes distortion of the dental impression due to the shape and/or configuration of the undercut, and not due to physicochemical properties of the impression material. Specifically, teeth in normal or treated conditions are usually angled, worn, and/or broken, to varying degrees, causing the presence of undercuts. For example, teeth are typically intentionally drilled down and/or cut by a dental practitioner in order to remove diseased material, such as removal of caries from a tooth, and in preparation of a dental prosthesis.
Intra-oral objects and features, such as teeth, gum, soft tissue, dental fixtures and prostheses of any kind, in normal or treated conditions, are characterized by color and, shape or structural, gradients. Clearly, there exist measuring and imaging limitations, even when applying a dental measuring and imaging technique featuring the use of multiple measuring and imaging devices, caused by the presence of undercuts and, color and shape or structural gradients which need to be addressed for successfully implementing a given dental measuring and imaging technique, in order for information obtained from the measuring and imaging data to be useful to a dental practitioner.
Implementing dental measuring and imaging systems operating with electromechanical or photogrammetric based registration procedures requires working under the above described constrained and limiting conditions. In order to obtain and use accurate and precise panoramic intra-oral measurement and imaging data and information in basic and advanced dental applications, measurements and images from multiple fields of view need to be pieced or merged together, using an appropriate best fit algorithm, for forming composite measurements and images, or maps, of the intra-oral objects and features, usually followed by converting measurements and image, and/or map, definition from source space into device space for displaying and storing the measurements and images, and/or maps, of the intra-oral objects and features. Even for a dental measuring and imaging technique providing high resolution single field of view measurements and images of intra-oral objects and features, any error in measuring and/or calculating locations and/or orientations of the measuring and imaging device relative to the intra-oral objects and features, causes propagation error in the registration procedure, translating to propagation error in the measurement and image piecing or merging procedure, thereby decreasing accuracy, precision, and utility, of final output data and information needed by the dental practitioner.
There is thus a need for, and it would be highly advantageous to have a method and system for real time intra-orally acquiring and registering three-dimensional measurements and images of intra-oral objects and features. Moreover, there is a need for such a method and system which are generally applicable to different categories of techniques of automatic three-dimensional shape measurement, imaging, and mapping of intra-oral objects and features, in the field of dentistry.
The present invention relates to a method and system for real time intra-orally acquiring and registering three-dimensional measurements and images of intra-oral objects and features.
According to the present invention, there is provided a method for real time intra-orally acquiring and registering three-dimensional measurements and images of intra-oral objects and features, the intra-oral objects and features are located inside the oral cavity of a dental patient, comprising the steps of: (a) establishing an intra-oral fixed global registration position inside the oral cavity of the dental patient, the intra-oral fixed global registration position is definable in terms of global coordinate space of the oral cavity, the global coordinate space is associated with a fixed global reference coordinate system, the global coordinate space includes a plurality of intra-oral local coordinate spaces in the oral cavity; (b) providing a measuring and imaging device for measuring and imaging the intra-oral objects and features located in the oral cavity; (c) selecting a field of view of the measuring and imaging device located at a global position in the global coordinate space of the oral cavity; (d) acquiring at least one three-dimensional measurement and image of the intra-oral objects and features located in the selected field of view of the measuring and imaging device, and, recording the global position of the measuring and imaging device relative to the intra-oral fixed global registration position, for forming at least one globally recorded three-dimensional measurement and image of the intra-oral objects and features located in the oral cavity; (e) repeating step (c) and step (d) for a plurality of said global positions and a plurality of the fields of view of the measuring and imaging device, for forming a plurality of the globally recorded three-dimensional measurements and images of the intra-oral objects and features located in the oral cavity of the dental patient; and (f) registering local coordinate space pixel positions in each of the plurality of globally recorded three-dimensional measurements and images with corresponding global coordinate space pixel positions, for forming a plurality of the three-dimensional measurements and images of the intra-oral objects and features located in the oral cavity of the dental patient which are registered relative to the same intra-oral fixed global registration position.
According to another aspect of the present invention, there is provided a system for real time intra-orally acquiring and registering three-dimensional measurements and images of intra-oral objects and features, where the intra-oral objects and features are located inside the oral cavity of a dental patient, comprising: (a) an intra-oral fixed global registration position inside the oral cavity of the dental patient, the intra-oral fixed global registration position is definable in terms of global coordinate space of the oral cavity, the global coordinate space is associated with a fixed global reference coordinate system, the global coordinate space includes a plurality of intra-oral local coordinate spaces in the oral cavity; (b) a measuring and imaging device for measuring and imaging the intra-oral objects and features located in the oral cavity, relative to the same intra-oral fixed global registration position; and (c) a mobile registration device for measuring and recording global positions and orientations of the measuring and imaging device, relative to the same intra-oral fixed global registration position.
According to further features in preferred embodiments of the invention described below, the intra-oral objects and features are selected from the group consisting of a part or entirety of a combination of teeth, gum, intra-oral soft tissue, bone matter, dental undercuts, and, dental fixtures and dental prostheses, permanent or removable, located inside the oral cavity of the dental patient.
According to further features in preferred embodiments of the invention described below, data and information extractable from the measuring and imaging the intra-oral objects and features located in the oral cavity relative to the same intra-oral fixed global registration position are used in a dental procedure selected from the group consisting of charting an oral condition, diagnosing an oral condition, and treating an oral condition, of the dental patient.
The method and system of the present invention serve as significant improvements over those currently used in the field of dental measuring and imaging, by providing an effective and efficient method and system for acquiring and registering three-dimensional measurements and images of intra-oral objects and features located in multiple fields of view of a measuring and imaging device, which are all registered to the same intra-oral fixed global registration position. This results in eliminating, or at least minimizing, propagation errors relating to piecing and merging together three-dimensional measurement and imaging data and information, especially needed for obtaining highly accurate and precise panoramic measurements and images of intra-oral objects and features located throughout the oral cavity of the dental patient.
Implementation of the method and system of the present invention involves performing or completing selected tasks or steps manually, automatically, or a combination thereof Moreover, according to actual instrumentation and equipment of a particular embodiment, several selected steps of the present invention could be implemented by hardware or by software on any operating system of any firmware or a combination thereof. For example, as hardware, selected steps of the invention could be implemented as a chip or a circuit. As software, selected steps of the invention could be implemented as a plurality of software instructions being executed by a computer using any suitable operating system.